PHP Convert string to array

@markus77

In PHP, strings are already byte arrays. So to put together the auth header for ProPay, see the following example:

$certStr = 'MyCertStr';
$termId = 'MyTermId';

$base64 = base64_encode($certStr.':'.$termId);
$authorization = 'Basic '.$base64;

//Output: "Basic TXlDZXJ0U3RyOk15VGVybUlk"